data = int(input())
if data>=30:
  print("Yes")
else:
  print("No") data = int(input()) data int(input()) int input() input if data>=30:
  print("Yes")
else:
  print("No") data>=30 data 30 print("Yes") print "Yes" print("No") print "No" data = int(input()) int(input()) data
data = int(input())
if data>=30:
  print("Yes")
else:
  print("No")